Acute Stress Disorder:
a stress disorder that occurs within four weeks following a traumatic event and that lasts for a minimum of two days and maximum of four weeks.

ADAA:
Anxiety Disorders Association of America

Addiction:
a preoccupation and compulsive use of an experience (food or gambling) or substance (alcohol or cocaine) despite the negative consequences. Often involves a loss of control and increasing tolerance for the substance. Not the same as dependence.

Agoraphobia:
a fear of being in a situation in which escape would be difficult or help would not be available in the case of a panic attack. Often results in increasing avoidance of certain things, places or situations.

Alarm Reaction (alarm and mobilization reaction):
the first stage of the so-called "general adaptation syndrome" by which the organism mobilizes its resources and defences to cope with stress.

Alcohol:
The consumption of alcoholic beverages may initially relieve anxiety for several hours. However, the post-intoxication effects of alcohol are generally thought to aggravate anxiety and panic. The use of alcohol may provoke anxiety and panic disorders.

Alexithymia:
a pattern of behavior and personality in which people are unable to express emotion and distress except through somatic symptoms.

Alienation:
the feeling of a lack of relationships or loss of relationships with others.

Alternative Medicine:
treatment techniques that are not currently accepted by the medical establishment. Such techniques generally have unknown scientific value.

Alpha 2 Agonists:
substances used in the treatment of anxiety that act on Alpha 2 auto receptors that results in decreased firing rate and decreased release of norepinephrine.

Alzheimer’s Disease:
a progressive, irreversible disorder attributed to the accumulation of certain proteins in the brain (especially amyloid).

Amnesia:
total or partial memory loss.

Amphetamine:
substance that produces a stimulating and energizing effect.

Amygdala:
a region of the brain thought to be very important in the fear response.

Anaesthesia:
Loss of all forms of sensation including pain, touch, and temperature.

Androgen:
hormone associated with the development and maintenance of male characteristics.

Anhedonia:
a decreased ability or inability to experience pleasure or joy.